Throw in LinkedIn, Twitter, Pinterest, Instagram and region specific social networks like Vkontakte and Sina Weibo and WeChat, and you’d be hard pressed to find anyone who’s online but isn’t on social media.

What has led to the rise of these social networks? What kind of people do they attract?

What is their psychology? What kind of content do they like to consume? And most importantly for bloggers and marketers – what works, what doesn’t on social media?

Facebook has become the ‘home base’ for most people online. While they may or may not use other networks, a majority maintain a presence on Facebook.

Popular: Used by 72% of all adult internet users in America.

More women users: 77% of online female users are on Facebook.

Younger audience: 82% of all online users between 18-29 are on Facebook

Younger users: 27% of all 16-24 year olds online are active members of Google+. In contrast, only 18% and 14% of 45-54 and 55-64 year olds are active on Google+ at the moment.

Large non-US user base: Only 55% of Google+ users are American. 18% are Indian and 6% are Brazilian. One reason for this international user base is Android’s popularity outside the US (since Google+ is baked right into Android).

Even income distribution: According to GlobalWebIndex.net, 22% of people in bottom 25% of income earners are on Google+. For the top 25% of income earners, this number is 24%, while for the mid 50% earners, this number is 23%. This means that nearly all levels of income earners are nearly equally represented on Google+.

If you’re targeting women with disposable income, head over to Pinterest.

For professionals with better education and income, use LinkedIn.

For everyone, go with Facebook.

The psychology of social media users

Facebook is a ‘closed’ network where your friends list will usually be limited to family, friends and acquaintances you’ve met in real life. Privacy is a big concern for Facebook’s users, and all posts are private by default.

This ultimately affects the way users interact with each other and with businesses on Facebook.

Facebook users have more close relationships. Pew found that heavy users of the platform are more likely to have a higher number of close relationships.

Facebook users are politically engaged and active.

To understand why people share or follow on Twitter, researchers at Georgia Tech and UMichigan analysed over 500M tweets over 15-months. They found that the three biggest reasons why people share/follow on Twitter are:

Network overlap: Your network is similar to your followers’ network.

User tweet-RT ratio: The number of tweets vs. the number of RTs for a user.